This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 70 |
| 7 | 490 |
| 8 | 2632 |
| 9 | 11606 |
| 10 | 46375 |
| 11 | 173362 |
| 12 | 618086 |
| 13 | 2123709 |
| 14 | 7086864 |
| 15 | 23085942 |
| 16 | 73761644 |
| 17 | 232002909 |
| 18 | 720819622 |
| 19 | 2218608551 |
| 20 | 6782480955 |